High-stability miniature inertial navigation device

Abstract

The utility model discloses a miniature inertial navigation device with high stability, which comprises an upper shell, a lower shell and a bottom plate, both the upper shell and the lower shell are of thin-wall shell structures with downward openings, the opening end of the upper shell is connected with the upper end of the lower shell to form an upper end cavity, and the opening end of the lower shell is connected with the bottom plate to form a lower end cavity. The upper end chamber and the lower end chamber are separated, an inertial device is arranged in the upper end chamber, an electrical component is arranged in the lower end chamber, the inertial device comprises an optical fiber gyroscope, and the electrical component comprises an MEMS accelerometer, a power supply, a core board and a GPS board card. According to the utility model, the purposes of electromagnetic shielding, thermal isolation and rapid conduction are achieved through the subdivision design of the inertial device and the electrical component, the signal interference of electromagnetic signals and thermal stress effects on the inertial device is solved, and the cost is reduced on the premise of ensuring that the product volume and weight meet the requirements. And stability and reliability of output precision of the inertial device are ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of navigation, in particular to a micro inertial navigation device with high stability. Background Art

[0002] With the development of economy and technology and the improvement of people's living standards, navigation technology has been widely used in people's production and life, bringing endless convenience to people's production and life. Therefore, ensuring the accuracy and stability of the navigation process has become one of the most important tasks of the navigation system.

[0003] An inertial navigation system (INS) is an autonomous navigation system that does not rely on external information and does not radiate energy to the outside. An inertial navigation system is a navigation parameter calculation system that uses gyroscopes and accelerometers as sensitive devices. The system establishes a navigation coordinate system based on the output of the gyroscope and calculates the speed and position of the vehicle in the navigation coordinate system based on the output of the accelerometer. The inertial navigation system belongs to the dead reckoning navigation method, that is, the position of the next point is calculated from the position of a known point based on the continuously measured heading angle and speed of the moving body, so that the current position of the moving body can be continuously measured.

[0004] With the rapid development of inertial device technology and the continuous updating of supporting requirements, micro inertial navigation devices have come into being. The requirements for the volume and weight of micro inertial navigation devices are also gradually increasing. However, when micro inertial navigation devices are miniaturized, electromagnetic interference problems often occur inside them, which greatly affects the accuracy and stability of the navigation process. Utility Model Content

[0005] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is: how to provide a high-stability micro inertial navigation device that can effectively reduce the internal electromagnetic interference problem, thereby effectively improving the accuracy and stability of the navigation process

[0006] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0007] A high-stability micro inertial navigation device comprises an upper shell, a lower shell and a bottom plate, wherein the upper shell and the lower shell are both thin-walled shell structures with openings facing downward, and the open end of the upper shell is connected to the upper end of the lower shell to form an upper end chamber, and the open end of the lower shell is connected to the bottom plate to form a lower end chamber, so that the upper end chamber and the lower end chamber are separated, and an inertial device is arranged in the upper end chamber, and an electrical component is arranged in the lower end chamber, wherein the inertial device comprises a fiber optic gyroscope, and the electrical component comprises a MEMS accelerometer, a power supply, a core board and a GPS board.

[0008] In this way, the present solution utilizes the upper shell, the lower shell and the bottom plate to divide the interior into two separated chambers, namely the upper chamber and the lower chamber. Meanwhile, only the inertial device, namely the fiber optic gyroscope, is installed in the upper chamber, and the electrical components are installed as a whole in the lower chamber, so that when the inertial navigation device is working, the electromagnetic signals generated by the circuit boards in the electrical components in the lower chamber will not generate a large electromagnetic interference to the fiber optic gyroscope in the upper chamber, and the fiber optic gyroscope will not generate a large electromagnetic interference to the electrical components in the lower chamber. That is, the inertial navigation device is structurally divided into two independent parts through the design of the double chambers, thereby avoiding mutual interference between the two parts. Meanwhile, the fiber optic gyroscope is installed in the upper chamber, and the electrical components are installed in the lower chamber. The outer shell can be used to cover the fiber optic gyroscope so that the fiber optic gyroscope is in an independent state, and the lower shell is used to cover the electrical components so that the electrical components are in an independent state, thereby effectively shielding the influence of external and self-electromagnetic signals on the fiber optic gyroscope and the electrical components. As a result, the micro inertial navigation system of the present invention will not be interfered by electromagnetic signals from other positions during operation, which greatly improves the accuracy and stability of the navigation process.

[0009] Preferably, the fiber optic gyroscope is mounted on the lower shell, and a threading hole is provided on the lower shell, and a signal line and a power line of the fiber optic gyroscope are inserted into the lower end chamber through the threading hole.

[0010] In this way, by providing the threading hole, it is convenient to introduce the signal line and power line of the fiber optic gyroscope into the lower end chamber, and finally lead them out from the lower shell to connect with external equipment.

[0011] Preferably, the threading hole is filled with conductive glue for sealing.

[0012] In this way, the threading hole is filled with conductive glue for sealing, so that the fiber optic gyroscope can be completely separated from the lower chamber, and the electromagnetic interference between them can be further reduced.

[0013] Preferably, the power supply includes a power board and a power module, the lower end of the power module is connected to the power board, and the upper end of the power module is in contact with the upper end of the lower shell.

[0014] In this way, the power module will generate a certain amount of heat when working. By fitting the upper end of the power module with the upper end of the lower shell, the heat generated by the power module can be quickly conducted outward through the lower shell, so as to reduce the temperature rise rate inside the inertial navigation device and ensure that the impact of temperature changes on the output accuracy stability of the inertial navigation device is within a controllable range.

[0015] Preferably, the MEMS accelerometer is provided with a plurality of pairs of aviation shock absorbers, each pair of aviation shock absorbers includes two aviation shock absorbers, and the two aviation shock absorbers of the same pair are respectively arranged on the upper side and the lower side of the MEMS accelerometer.

[0016] In this way, by setting up an aviation shock absorber to isolate the MEMS accelerometer from vibration, the influence of temperature changes and external vibrations on the output accuracy stability of the MEMS accelerometer can be effectively reduced.

[0017] Preferably, the MEMS accelerometer is provided with three pairs of aviation shock absorbers, and the three pairs of aviation shock absorbers are mutually staggered and arranged on the MEMS accelerometer.

[0018] In this way, three pairs of aviation shock absorbers are mutually offset and arranged on the MEMS accelerometer, which can effectively isolate the vibration of the MEMS accelerometers at different positions and ensure the vibration isolation effect.

[0019] Preferably, one pair of aviation shock absorbers is arranged at the middle position of one side of the MEMS accelerometer, and the other two pairs of aviation shock absorbers are arranged at the two end positions of the other side of the MEMS accelerometer.

[0020] Preferably, a clearance gap is also provided on the power board, and the MEMS accelerometer is arranged at the clearance gap.

[0021] In this way, by providing a clearance gap and arranging the MEMS accelerometer at the clearance gap, the volume of the entire device in the vertical direction can be reduced, thereby achieving a miniaturized design.

[0022] Preferably, the upper shell and the lower shell, and the lower shell and the bottom plate are connected via fasteners.

[0023] Preferably, a connector interface and an output antenna interface are also fixedly connected to the outer side surface of the lower shell.

[0024] Compared with the prior art, the utility model has the following advantages:

[0025] 1. The utility model achieves the purpose of electromagnetic shielding, thermal isolation and rapid conduction through the compartment design of inertial devices and electrical components, and solves the signal interference of electromagnetic signals and thermal stress on inertial devices. The inertial navigation device has an overall size of 78mm×80mm×77mm and a total weight of no more than 600g. On the premise of ensuring that the product volume and weight meet the requirements, the stability and reliability of the output accuracy of the inertial device are guaranteed.

[0026] 2. The volume of the utility model product is reduced by about 10%, the weight is reduced by about 15%, the output accuracy stability and reliability of the inertial device are improved by about 30%, and the heading accuracy of the navigation is not greater than 0.5° / h (1σ), and the horizontal accuracy is not greater than 0.05° (1σ). BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the structure of the high-stability micro inertial navigation device of the utility model;

[0028] Figure 2 It is a cross-sectional view of one side of the high-stability micro inertial navigation device of the utility model;

[0029] Figure 3 It is a cross-sectional view of the other side of the high-stability micro inertial navigation device of the utility model;

[0030] Figure 4 This is a schematic diagram of the installation of a power module in a high-stability micro inertial navigation device of the utility model;

[0031] Figure 5 The present invention is a schematic diagram of the structure of a power supply board and a MEMS accelerometer in a high-stability micro inertial navigation device.

[0032] Explanation of the accompanying drawings: upper shell 1, lower shell 2, bottom plate 3, connector interface 4, output antenna interface 5, fiber optic gyroscope 6, power module 7, power board 8, MEMS accelerometer 9, core board 10, GPS board 11, aviation shock absorber 12. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model clearer, the technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. The components of the embodiment of the utility model generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiment of the utility model provided in the drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents the selected embodiment of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the utility model.

[0034] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the utility model, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the utility model product is usually placed when used, which is only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] As attached Figure 1 To the attached Figure 3 As shown, a high-stability micro inertial navigation device includes an upper shell 1, a lower shell 2 and a bottom plate 3. The upper shell 1 and the lower shell 2 are both thin-walled shell structures with openings facing downward, and the open end of the upper shell 1 is connected to the upper end of the lower shell 2 to form an upper end chamber, and the open end of the lower shell 2 is connected to the bottom plate 3 to form a lower end chamber. The upper shell 1 and the lower shell 2, and the lower shell 2 and the bottom plate 3 are connected by fasteners to separate the upper end chamber and the lower end chamber, and an inertial device is arranged in the upper end chamber, and an electrical component is arranged in the lower end chamber, wherein the inertial device includes a fiber optic gyroscope 6, and the electrical component includes a MEMS accelerometer 9, a power supply, a core board 10 and a GPS board 11. A connector interface 4 and an output antenna interface 5 are also fixedly connected to the outer side of the lower shell 2 for connecting with external devices.

[0036] In this embodiment, the fiber optic gyroscope 6 is mounted on the lower housing 2. A threading hole is provided on the lower housing 2. The signal line and power line of the fiber optic gyroscope 6 are inserted into the lower end chamber through the threading hole.

[0037] In this way, by providing the threading hole, it is convenient to introduce the signal line and power line of the fiber optic gyroscope 6 into the lower end chamber, and finally lead them out from the lower shell 2 to connect with external equipment.

[0038] In this embodiment, the threading hole is filled with conductive glue for sealing.

[0039] In this way, the threading hole is sealed by filling conductive glue, so that the fiber optic gyroscope 6 can be completely separated from the lower chamber, and the electromagnetic interference between them can be further reduced.

[0040] As attached Figure 4 As shown, in this embodiment, the power supply includes a power board 8 and a power module 7, the lower end of the power module 7 is connected to the power board 8, and the upper end of the power module 7 is in contact with the upper end of the lower shell 2.

[0041] In this way, the power module 7 will generate a certain amount of heat when working. By fitting the upper end of the power module 7 with the upper end of the lower shell 2, the heat generated by the power module 7 can be quickly conducted outward through the lower shell 2, so as to reduce the temperature rise rate inside the inertial navigation device and ensure that the influence of temperature changes on the output accuracy stability of the inertial navigation device is within a controllable range.

[0042] As attached Figure 5 As shown, in this embodiment, a plurality of pairs of aviation shock absorbers 12 are provided on the MEMS accelerometer 9 , each pair of aviation shock absorbers 12 includes two aviation shock absorbers 12 , and the two aviation shock absorbers 12 of the same pair are respectively provided on the upper side and the lower side of the MEMS accelerometer 9 .

[0043] In this way, by providing the aviation shock absorber 12 to isolate the MEMS accelerometer 9 from vibration, the influence of temperature change and external vibration on the output accuracy stability of the MEMS accelerometer 9 can be effectively reduced.

[0044] In this embodiment, three pairs of aviation shock absorbers 12 are disposed on the MEMS accelerometer 9 , and the three pairs of aviation shock absorbers 12 are disposed on the MEMS accelerometer 9 in a mutually staggered manner.

[0045] In this way, the three pairs of aviation shock absorbers 12 are mutually staggered and arranged on the MEMS accelerometer 9, which can effectively isolate the vibration of the MEMS accelerometers 9 at different positions and ensure the vibration isolation effect.

[0046] In this embodiment, one pair of aviation shock absorbers 12 is disposed at the middle position of one side of the MEMS accelerometer 9 , and the other two pairs of aviation shock absorbers 12 are disposed at the two end positions of the other side of the MEMS accelerometer 9 .

[0047] In this embodiment, a clearance gap is also provided on the power board 8, and the MEMS accelerometer 9 is arranged at the clearance gap.

[0048] In this way, by providing a clearance gap and arranging the MEMS accelerometer 9 at the clearance gap, the volume of the entire device in the vertical direction can be reduced, thereby achieving a miniaturized design.

[0049] This solution utilizes an upper shell 1, a lower shell 2 and a bottom plate 3 to divide the interior into two separated chambers, namely an upper chamber and a lower chamber. Meanwhile, only an inertial device, namely a fiber optic gyroscope 6, is installed in the upper chamber, and the electrical components are installed as a whole in the lower chamber, so that when the inertial navigation device is working, the electromagnetic signals generated by the circuit boards in the electrical components in the lower chamber will not generate a large electromagnetic interference to the fiber optic gyroscope 6 in the upper chamber, and the fiber optic gyroscope 6 will not generate a large electromagnetic interference to the electrical components in the lower chamber. That is, the inertial navigation device is structurally divided into two independent parts through the design of the double chambers, thereby avoiding mutual interference between the two parts. Meanwhile, the fiber optic gyroscope 6 is installed in the upper chamber, and the electrical components are installed in the lower chamber. The outer shell can be used to cover the fiber optic gyroscope 6 so that the fiber optic gyroscope 6 is in an independent state, and the lower shell 2 is used to cover the electrical components so that the electrical components are in an independent state, thereby effectively shielding the influence of external and self-electromagnetic signals on the fiber optic gyroscope 6 and the electrical components. As a result, the micro inertial navigation system of the present invention will not be interfered by electromagnetic signals from other positions during operation, which greatly improves the accuracy and stability of the navigation process.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit the technical solution. Ordinary technicians in this field should understand that those modifications or equivalent replacements of the technical solution of the utility model without departing from the purpose and scope of the technical solution of the utility model should be included in the scope of the claims of the utility model.

Claims

1. A high-stability micro inertial navigation device, characterized in that: The invention comprises an upper shell, a lower shell and a bottom plate, wherein the upper shell and the lower shell are both thin-walled shell structures with openings facing downward, and the open end of the upper shell is connected to the upper end of the lower shell to form an upper end chamber, and the open end of the lower shell is connected to the bottom plate to form a lower end chamber, so that the upper end chamber and the lower end chamber are separated, and an inertial device is arranged in the upper end chamber, and an electrical component is arranged in the lower end chamber, wherein the inertial device comprises a fiber optic gyroscope, and the electrical component comprises a MEMS accelerometer, a power supply, a core board and a GPS board.

2. The high-stability micro inertial navigation device according to claim 1, characterized in that: The fiber optic gyroscope is mounted on the lower housing, and a threading hole is provided on the lower housing. The signal line and the power line of the fiber optic gyroscope pass through the threading hole and enter the lower end chamber.

3. The high-stability micro inertial navigation device according to claim 2, characterized in that: The threading holes are filled with conductive glue for sealing.

4. The high-stability micro inertial navigation device according to claim 1, characterized in that: The power supply includes a power board and a power module. The lower end of the power module is connected to the power board, and the upper end of the power module is in contact with the upper end of the lower shell.

5. The high-stability micro inertial navigation device according to claim 1, characterized in that: The MEMS accelerometer is provided with a plurality of pairs of aviation shock absorbers, each pair of aviation shock absorbers includes two aviation shock absorbers, and the two aviation shock absorbers of the same pair are respectively arranged on the upper side and the lower side of the MEMS accelerometer.

6. The high-stability micro inertial navigation device according to claim 5, characterized in that: The MEMS accelerometer is provided with three pairs of aviation shock absorbers, and the three pairs of aviation shock absorbers are mutually staggered and arranged on the MEMS accelerometer.

7. The high-stability micro inertial navigation device according to claim 6, characterized in that: One pair of aviation shock absorbers is arranged at the middle position of one side of the MEMS accelerometer, and the other two pairs of aviation shock absorbers are arranged at the two end positions of the other side of the MEMS accelerometer.

8. The high-stability micro inertial navigation device according to claim 4, characterized in that: A clearance gap is also provided on the power board, and the MEMS accelerometer is arranged at the clearance gap.

9. The high-stability micro inertial navigation device according to claim 1, characterized in that: The upper shell and the lower shell, and the lower shell and the bottom plate are connected via fasteners.

10. The high-stability micro inertial navigation device according to claim 1, characterized in that: A connector interface and an output antenna interface are also fixedly connected to the outer side surface of the lower shell.

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